Background: Despite interest in early treatment of schizophrenia, premorbid and prodromal symptomatology remain poorly delineated.
Aims: To compare pre-illness symptomatology in patients at high risk of schizophrenia who progress to illness with that of high-risk subjects who remain well and with normal controls.
Method: Using Present State Examination (PSE) data, symptomatic scales were devised from participants of the Northwick Park Study of first-episode schizophrenia and scores were compared on the first and last PSEs of participants of the Edinburgh High Risk Study.
Results: At entry, when still well, high-risk individuals who subsequently became ill (mean time to diagnosis 929 days; s.e.=138 days) scored significantly higher on'situational anxiety', 'nervous tension', 'depression', 'changed perception'and 'hallucinations'than those remaining well and normal controls, who did not differ. With illness onset, affective symptomatology remained high but essentially stable.
Conclusions: In genetically predisposed individuals, affective and perceptual disorders are prominent before any behavioural or subjective change that usually characterises the shift to schizophrenic prodrome or active illness.